Effective treatments for patients with cancer represented a major challenge in the medical field. The current regimen of surgical resection, external beam radiation therapy, and systemic chemotherapy has been partially successful in some kinds of malignancies. In some malignancies, such as brain malignancies, this regimen produces a median survival of less than one year. Though effective in some kinds of cancers, the use of systemic chemotherapy reached only minor success in the treatment of cancers of the colon-rectum, esophagus, liver, pancreas, and kidney, and skin. A major problem with systemic chemotherapy for the treatment of these types of cancers is that the systemic drug release required for control over tumor growth cell.
Efforts to improve delivery of chemotherapeutic agents to the tumor site have resulted in advances in organ-directed chemotherapy, for example, by continuous systemic infusion. However, continuous infusions of anticancer drugs generally have not shown a clear benefit over pulse or short-term infusions. Some of the prior arts are as follows,
US20070053845 discloses a drug delivery system of two different therapeutic agents by means of a core nanoparticle with one therapeutic agent and an outer layer coating of the said core as a shell nanoparticle with second therapeutic agent. The coating of the therapeutic agent as the outer shell delivers the drugs in the faster or even in uncontrollable rate, when compared to the drug delivery from the core.
WO2007069272 discloses a composition for cancer therapy comprises nanoparticles of at least one anticancer drug and at least one polymer. WO2007119601 discloses a pharmaceutical composition with the nanoparticles of platelet-derived growth factor (PDGF) receptor tyrosine kinase inhibitor.
Most of the FDA approved nanoformulations and other drug delivery systems reported till date are single agent delivery vehicles which pose structural constraints to encapsulate and release multiple payloads in optimal concentrations at the tumor site. Encapsulation of more than one drug in the same nano-carrier may elicit undesirable drug-drug interaction which might alter the pharmacology of both the drugs, resulting in inefficacy of the drugs.
However, there remains a need for a drug delivery system for delivering combination therapies so that each agent provides the desired maximal effect. Moreover, the drug delivery system must deliver multiple therapeutic agents and independently release therapeutic agents toward targeted diseased sites.